Dopaminergic regulation of aldosterone secretion has been well demonstrated in normal subjects as well as patients with PA. We have shown that D2 receptor can down-regulate the transcription of aldosterone synthase (CYP11B2) via a specific PKC isoform and probably intracellular calcium level. Furthermore, there is a reciprocal change of the mRNA of D2 receptor and CYP11B2 in APA. D2 receptor has also been demonstrated in other neuroendocrine tumors, eg., pheochromocytoma, prolactinoma, GH-secreting adenoma ect. [Camacho & Mazzone 1999] Administration of D2 agonist, bromocriptin (BMC), is a standard treatment of prolactinoma, either for pre-operative reduction of the tumors or for non-surgical patients [Chattopadhyay et al., 2005]. Reduction or shrinkage of prolactinoma has been observed in patients treated with BMC [Biswas et al., 2005]. Anti-proliferative effect and apoptosis of BMC have been demonstrated in several cell lines [Wasko et al., 2004]. Recently, we also demonstrated that BMC, in addition to decrease aldosterone secretion and expression of CYP11B2, could inhibit cell proliferation of H295 cells, an adrenocortical carcinoma cell line, with a down-regulation of ERK. In this context, we propose that BMC may be an alternative treatment of PA, both APA and BAH.